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Appendix F.

is also used on bar work generally. Its description will be under-
stood by reference to Plate XIX. and to Fig. 908. It may be
traversed in any of three ways: (i) by hand, (2) by self-acting
shaft, (3) by leading screw. The hand traverse is obtained by
handwheel i, wheels 2 and 3, and rack pinion 4. The self-act is
taken from shaft h through pinions 9 and TO, worm and wheel
5 and 6, and wheels 7, 3, and 4. The worm wheel is carried in a
cradle 12, hinged round the shaft //, and held in position by a
stop or trigger 13. Whenever the hand traverse or cross feed are
to be used, the traverse worm 5 is released by dropping the cradle
by handle 8, after releasing catch 13. The clamp n fixes the
saddle for heavy tooling.

Hexagon LaJLtte.


FAQ. 90S.

As there are four tools to this head, so also are there four
release stops to the traverse motion, each of which may be turned
into position by hand. The stops ar$ seen in Figs. 905-6,
Plate XIX., being carried on a block projecting from the leflf
end of saddle. They may be adjusted longitudinally, so as to
strike the rod 15 at any given position of the saddle, the latter
being also adjustable for the same purpose. The strike causes 16
to move a spindle to the right, and operate trigger 13, releasing
the worm cradle and stopping the saddle.

A second worm 17 (Plate XIX.) drives a wheel 18, and thus
the cross feed is obtained through wheels 19, 20, 21, and screw 22 ;
or hand feed may be given by wheel 24, if trigger 23 be moved
rightwards by hand to drop the cross-feed worm cradle. A
bar 25 carries four stops 26, set in convenient positions, and each.